Join tables?

I have 3 tables: Companies, Addresses and Productions. I made a view where these tables is joined by keyfield 'Key': CREATE VIEW TOTAL (COMPANY, ADDRESS, PRODUCTION) AS SELECT C.COMPANY_NAME, A.ADDRESS, P.PRODUCTION FROM COMPANIES C, ADDRESSES A, PRODUCTIONS P WHERE C.KEY = A.KEY AND C.KEY = P.KEY; But when I try to get just Company Name and Address with SELECT COMPANY, ADDERSS FROM TOTAL WHERE COMPANY = 'IBM' I get more then one row because the KEY field is multiply defined in PRODUCTIONS table (that company is develops a lot of goods).

How to create view to avoid duplicates? GROP BY expression does not work because I really have fields as NAME1||NAME2 and F1*8/2 and so on.

Thanks for any help.

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Nick Maximov
<maxs_at_adnserv.kaija.spb.su>